Wireless sensor devices are used in a variety of applications including cardiovascular health monitoring of patients. In many of these applications, a wireless sensor device is attached directly to the user's skin (e.g. near the chest area) to measure certain data such as cardiovascular time series. Cardiovascular time series are certain physiological signal features used to monitor physiological as well as pathological changes in a variety of patients.
Cardiovascular time series are extracted on a beat-to-beat basis from an electrocardiogram (ECG) signal and on a pulse-to-pulse basis from pulse oximetric photoplethysmogram (PPG) or noninvasive blood pressure waveforms. Motion and noise artifacts corrupt the raw signal waveforms and the derived cardiovascular time series as well. Conventional methods to accurately detect/reduce artifacts suffer from limitations that include not being optimal for in-band noise and prolonged artifact events, failing to preserve absolute time, failing to ensure artifact free in the derived time series, and not being applicable to various types of motion artifacts. Therefore, there is a strong need for a cost-effective and efficient solution that overcomes the aforementioned issues. The present invention addresses such a need.